Vehicle-brake.



M. POTTER.

VEHICLE BRAKE.

APPLICATION FILED Arms, 1915.

1214,71 3. Patented Feb. 6, 1917.

A INVENTOR i 32 E By Attorneys,

Mann mm MORGAN POTTER, OF BEACON, NEW YORK.

VEHICLE-BRAKE.

To all whom it may concern.-

,Be it' known that I, MORGAN POTTER, a citizen of the United .States, residing at. Beacon, in'the county of Dutchess and State of New York, have invented certain new and useful Improvements in Vehicle-Brakes, of which the following isa specification. This invention provides an improved construction of internal expansion brake applicable to vehicles of various types, and particularly to carriages and wagons.

A drum is fastened to the vehicle wheel, and within it are brake shoes which are held stationary by engagement with a dividedshell or disk which is fastened on the axle. The shoes are drawn in by springs and are pressed out by eccentric dogs con nected adjustably to an equalizing lever, which in turn is engaged by a cranked rocklever an arm on which is engaged by' the operating rod.

The features of improvement are hereinafter set forth and defined in the claims.

In the accompanying drawings, Figure 1 is a sectional elevation, the axle and crank wrist of the operating rock-lever being in section, and the remaining parts in elevation looking from the middle of the axle out- ,wardly; Fig. 2 is a vertical section in planes indicated by the line 22 in Fig. 3; Fig. 3 is a vertical section on the line 3-3 in Fig. 2 looking in the contrary direction 1 from Fig. 1 ,Fig. 4 is a perspective view of the brake mechanisms looking outwardly and rearwardly; Fig. 5 is a perspective of one of the eccentric dogs; Fig. 6 is across-section through a spoke on .the line 66 in Fig. 2.

Referring to the drawings, A indicates one of the hind wheels of the vehicle, here shown as a carriage or wagon, a a being the, spokes and I) being the hub, and B is the" axle: To the wheel A is fastened a brake drum C; the fastening may be accomplished in any suitable way by attaching thedrum either to the spokes or to the hub. The

drum is closedon the'wheel side bya web 0.

Y Within the drum are brake shoes D D,

clearly shown in Fig. 3, which are held nonpecifieation of Letters Patent.

wooden spokes, it is preferable to extend Patented Feb. e, 1917.

Application filed April 3, 1915. Serial No. 18,972.

For pressing out the shoes D D to engage them with the drum, means are provided whereby while each shoe is pressed outwardly independently of the other,.the reactive pressure is transmitted to the oppo-' site shoe, so that their outward pressures are equalized. In the. preferred construction shown the shoes are pressed out by levers or dogs F F pivoted t studs (Z d whichare fastened to the dislg and bearing on one arm against the shoe, while the opposite arm has a pin 6 passing out through a slot f in the disk and engaged by a rod g. The two rods 7 g are connected to an equalizing lever Gr which is hung on a crank wrist h of a crank rock-lever H, which as shown in Fig. i is suitably supported as by being mounted to turn or rock in bearing brackets, one of 5 which is shown at I, being fastened by clamps i to the axle. Only one end portion of the rock-lever H is shown with its crank it for the brake on one wheel, the other bein a-duplicate ofthe one here shown.

0n t e rock-lever H-is clamped or other- 0 wise fastened an arm J which is engaged by the usual brake operating pull rod K, which extends forward and connects in any usual manner with a brake-lever or treadle so that the pull thereon will apply the brake. In operation, a pull in the direction of the arrow Fig. 3 on the rod K, acts through the arm J to rock the lever H and thereby swing its cranks it forward; thus the crank wrist k is moved forward and carries for-' ward the equalizing lever G, the opposite arms of which exert alike pull on the two rods 9 g which in turn rock the dogs F F, so that the latter thrust outwardly the shoes D D. On the cessation .of the pull on the rod 9 K the parts are restored to their normal position. The brake shoes are retractedby springs L L which are attached to pins projecting inwardly from the disk E. The general construction and being now understood, somedf the preferred details of construction will be explained.

For attaching ..the drum 0 to'any ordinary wagon or carriage wheel having the web 0 outward toward the wheel and.

provide it .with a hub portion 0', Fig. 2, fitting over the inner side of the wheel hub and centered thereon. Through this hub portion holes are formed preferably alined 1 operation arrangement of staggered spokes is employed. A bolt j is put through a hole bored in this spoke and through the coinciding hole in the hub portion 0 to fasten the ,drum firmly to the spoke. While the drum might be clamped directly against the inner face of the spokes, yet it ispreferable to place between them a spacer 0r shim is, best shown in Fig. 6', which supports the spoke, relieves side strain on the bolt, and prevents splitting of the spoke by such side strain. As sometimes there is some irregularity in the spokes, this may be compensated for by selecting shims of different thicknesses. Also by the selection of thicker or thinner'shims the drum may be set farther from or closer to the wheel in order to bring the brake into the desired plane.

For fastening the disk E upon the axle it is not onlymade in halves, but each half has a hub portion or collar Z fitting the squared portion of the axle, as shown in Figs. 1 and 2, and fastened thereto by a' clamp preferably of the usual clip and bar type as shown; the clip is of rectangular U-sh'ape fitting three sides of the square with a cross-barn on the fourth side, the

.legs of the U having screwthreaded extenslons passing through holes in the bar and forming bolts receiving the clamping ends. The neck Z is provided ithan outturned lip Z, Fig. 2, to keep the clip or clampfrom slipping 0E. For the further securing of the disk halves to the axle, they are formed with ears p which are clamped together by bolts 39'.

- lubricated with graphite.

For connecting the shoes D to the disk ,E in such manner that the shoes are held from rotation while being permitted to freely move out toward the drum and inward therefrom, the shoes are formed with gins of the slot and hold the shoe in place.

Each pin is preferably fastened to the disk by being screwed into it against a neck or shoulderand locked by a nut s on the outside with preferably an intervening spring .washer s. r

The brake shoes are preferably faced with a facing band D, which may be a fabric of wire, canvas and asbestos, such as iscommonly used for facing brake shoes, and

. Each of the "shoe operating levers or dogs F preferably has an eccentric face. Instead of having the eccentric portion of thislever directly engaging the shoe, an" intervening rocker shoe M is provided which is pivoted by a, pint to the brake shoe D. This rocker piece has an inner face which is of the same curve as the eccentric outer face of the dog- F. For keeping, the parts in correct engagement notwithstanding any side play, the dog is formed with flanges f embracing the rocker piece so that the latter is confined in the channel between the two flanges. Thus the shoe is held against pulling outward away from the disk by-the'flanges f and the heads on the screw pins 1- 1".

For adjusting'the pivotal axes on which the dogs F turn, each pivot pin dis made adjustable in a slot in the disk E. The slot extends innearlyradial direction, as shown in dotted lines in Fig. 1. The pin D has fiat. sidesembraced by the sides of the slot to keep it from turning and is clamped in any position to which it may be adjusted by means of a nut 03. o

The pin e is best made integral with the dog F, as shownin Fig. 5; Its outer portion receives an eye formed on the end of the link 9, the latter being held in place by means of a cotter pin put through a hole in the pin 6 near'its outer end. Each of the links 9 is adjustable in length. This is accomplished by making the link in two sections, the section 9 being a threaded rod and the section 9 having a threaded sleeve into which the rod screws and terminating in a fork which embraces the end of theequalizing lever G, a headed pin it being put through and fastened by a cotter pin. To adjust the length of the link this cotter pin and pin a are removed and the sleeve 9 J screwed out or in on the threaded rod, after 1 which the pivoted pinis replaced, thus preventing any relative turning of the members :of the link and so preserving the adjust- Iament. The bearing bracket I for-the rock-lever H is fastened on the squared part of the axle by means of two clampsi i of the clip type, as shownin Fig. 4.

It will be observed that each half of the disk E carries independently the parts constituting one half of the brake mechanism, so that by first removing the clamp m either half of the disk may be taken out of the drum, thus carrying with '-it the one brake shoe, dog F and connected parts, and without disturbingthose attached to the other half of the disk.

The brake shoes while held against rotation by the pins 1' are otherwise freely mounted, so that by the yielding of the springs L they may readily adapt themselves to the surface of "the drum when pressed outwardly by the levers F. Each shoe is of a length somewhat less than half the circle, and is unsymmetrical to the-extent shown, its end with which any point on the drum fi st makes contact being extended farther than its opposite end beyond the point of application of the expanding .pres

sure to the shoe. This has the effect of securing an even shoecontactwith the drum and a uniform distribution of pressure for the whole length of the brake shoe, thereby giving a substantially uniform braking effeet over its entire surface. It is found that with a symmetrical shoe the end which first receives the rub of the drum wears faster than the remaining portion, and this uneven wear is avoided by .thus prolonging this end portion of theshoe.

The improved brakethus described is simple ll'l'COIlSlJfLlClSlOD, has an even and moderately applied brake action which may be readily graduated at will, is not liable to derangement by wear, is readily adjustable to adapt it to the requirements of practice, and is easily applied to existing vehicles.

I claim as my invention 1. A vehicle'hrake comprising in combination a drum attached to the wheel, a stato the shoe-gaging means.

2. The, combination of a brake drum, a stationary shell, a brake shoe having nonrotative engagement with the shell, springs for drawing the brake shoe inwardly, and a lever pivoted eccentric-ally to the shell and having an eccentric face for forcing the shoe outwardly against the drum.

3. The combination of a brake drum, a stationary shell, a brake shoe having nonrotative engagement with the shell, springs for drawing the brake shoe inwardly, and an eccentric faced lever pivoted eccentrically to the shell and engaging the middle portion of the shoe for forcing the shoe outwardly.

.4. The combination of a brake drum, a stationary shell, a' brake shoe having nonrotative engagement with the shell, springs for drawing the brake shoe inwardly, an eccentric faced lever pivotally supported on the shell for forcing the shoe outwardly, and a rocking piece receiving the thrust of said lever and pivotally engaging the shoe.

5. The combination of a brake drum, a stationary shell," a brake shoe having nonrotative engagement with the shell, springs for drawing the brake shoe inwardly, an

eccentric, faced lever pivotally supported on the shell for forcing the shoe outwardly, and

a rocking piece receiving the thrustof said lever and pivotallyv engaging the shoe, said lever having flanges between which the rocking piece is engaged.

6. The combination of a braxe drum, a stationary shell, a brake shoe having nonrotative engagement with the shell, springs for drawing the brake shoe inwardly, a lever for forcing the brake shoe outwardly, and a pivotal stud for said lever engaging said shell and adjustable toward and from the drum.

7. The combination of a brake drum, a stationary shell, a brake shoe having nonrotative engagement with the shell, springs for drawing the brake shoe inwardly, a' lever for forcing the brake shoe outwardly, and a "pivotal stud for said lever engaging a radially disposed slot in said shell whereby it may be set outwardly of inwardly to adjust the lever, and means for clamping it in place. a

8'. The combination with a brake drum, of a stationary shell, brake shoes within the drum having non-rotative attachmentto the shell, levers for pressing out the respective shoes pivotally connected to the shell, each lever acting against one shoe, rods engaging said levers, an equalizing lever connecting said rods, and a brake operating part engaging the middle part of said lever.

9. The combination with .a brake drum, of a stationary shell, brake shoes within the drum having non-rotative attachment to the shell, levers for pressing out the respective shoes pivotally connected to the. shell, each lever acting against one shoe, rods engaging said levers, an equalizing lever connecting said rods, either of said rods adjustable in length, and a brake operating part engaging the middle part of said lever.

10. The combination with a brake drum, of a stationary shell, brake shoes within the drum having non-rotative attachment to the shell, levers for pressing out the shoes pivotally connected to the shell, rods engaging of a stationary shell, brake shoes within the drunfhaving n'on-rotative attachment to the shell, :levers for pressing out the shoe pivotally connected to the shell, rods engaging said levers, an equalizing'lever connecting .said rods, a/bralke operating shaft having a crank arm engaging said equalizing lever, an operating arm, and axsupporting bracket fastened to the axle affording a bearing for, said brake operating shaft.

12. In a vehicle brake of the internal expansion type, a drum attached tothe wheel, 1

a shell fastened to the axle, and brake-shoes carried by such shell, combinedwith means engaging the medial portions of such shoes for pressing them out against the drum, the

shoes being unsymmetrical their ends first rubbed by the drum being more distant from the point of application of such outward in the shoes laterally, whereby each shoe is confined at three points against lateral displacement due to end play of the wheel.

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnesses.

' MORGAN POTTER.

Witnesses:

Enwn E. STRONG, JOHN N. NI HOLL 

